--- permalink: pandas/sankey-diagram/ description: How to make Sankey Diagrams in Python with Plotly. name: Sankey Diagram has_thumbnail: true thumbnail: thumbnail/sankey.jpg layout: base language: pandas title: Sankey Diagram | Plotly display_as: basic has_thumbnail: true ipynb: ~notebook_demo/150 order: 13 page_type: u-guide --- {% raw %}

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Version Check

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In [1]:
import plotly
plotly.__version__
Out[1]:
'2.4.1'

Basic Sankey Diagram

In [2]:
import plotly.plotly as py

data = dict(
    type='sankey',
    node = dict(
      pad = 15,
      thickness = 20,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label = ["A1", "A2", "B1", "B2", "C1", "C2"],
      color = ["blue", "blue", "blue", "blue", "blue", "blue"]
    ),
    link = dict(
      source = [0,1,0,2,3,3],
      target = [2,3,3,4,4,5],
      value = [8,4,2,8,4,2]
  ))

layout =  dict(
    title = "Basic Sankey Diagram",
    font = dict(
      size = 10
    )
)

fig = dict(data=[data], layout=layout)
py.iplot(fig, validate=False)
Out[2]:

Create Sankey Canvas

In [3]:
import plotly.graph_objs as go

plotly.offline.init_notebook_mode()

data = dict(
    type='sankey',
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh"
  )

layout =  go.Layout(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10
    )
)

Add Nodes

In [4]:
import plotly.graph_objs as go

import urllib, json

plotly.offline.init_notebook_mode()

url = 'https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json'
response = urllib.urlopen(url)
data = json.loads(response.read())

data_trace = dict(
    type='sankey',
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh",
    node = dict(
      pad = 15,
      thickness = 15,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label =  data['data'][0]['node']['label'],
      color =  data['data'][0]['node']['color']
    )
)

layout =  go.Layout(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10
    )
)
In [5]:
import plotly

import urllib, json

plotly.offline.init_notebook_mode()

url = 'https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json'
response = urllib.urlopen(url)
data = json.loads(response.read())

data_trace = dict(
    type='sankey',
    width = 1118,
    height = 772,
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh",
    node = dict(
      pad = 15,
      thickness = 15,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label =  data['data'][0]['node']['label'],
      color =  data['data'][0]['node']['color']
    ),
    link = dict(
      source =  data['data'][0]['link']['source'],
      target =  data['data'][0]['link']['target'],
      value =  data['data'][0]['link']['value'],
      color =  data['data'][0]['link']['color'],
      label =  data['data'][0]['link']['label']
  ))

layout =  dict(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10
    )
)

fig = dict(data=[data_trace], layout=layout)
plotly.offline.iplot(fig, validate=False)

Style Sankey Diagram

In [7]:
import plotly

import urllib, json

plotly.offline.init_notebook_mode()

url = 'https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy_dark.json'
response = urllib.urlopen(url)
data = json.loads(response.read())

data_trace = dict(
    type='sankey',
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh",
    node = dict(
      pad = 15,
      thickness = 15,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label =  data['data'][0]['node']['label']
    ),
    link = dict(
      source =  data['data'][0]['link']['source'],
      target =  data['data'][0]['link']['target'],
      value =  data['data'][0]['link']['value'],
      label =  data['data'][0]['link']['label']
  ))

layout =  dict(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10,
      color = 'white'
    ),
    plot_bgcolor = 'black',
    paper_bgcolor = 'black'
)

fig = dict(data=[data_trace], layout=layout)
plotly.offline.iplot(fig, validate = False)

Reference

See https://plot.ly/python/reference/#sankey for more information and options!

{% endraw %}